Debunked: Belfort Group "Case Orange" conclusions & recommendations

lee h oswald said:
So the additional soot helps with contrail formation. Why?
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It provides additional condensation nuclei.

Is there a point to these questions? I'm happy to explain contrails, but you could just be reading up on them elsewhere.

[Edit] The additional nuclei mean there are more initial ice crystals formed. The ice crystals can only form during the initial high-humidity stage with lasts only a second or so. The more ice crystals are formed, the higher the persistence and optical density of the contrail (assuming ambient humidity is high enough for the ice crystals to grow)
 
lee h oswald said:
Not according to the only full scale experiment ever held.
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You mean 9/11? It did not get net warmer, there was an increase in the diurnal temperature range (i.e. it was warmer in the daytime, and colder at night). That's a rather small data set unfortunately, and current thinking is that it might just have been odd weather on those days:

http://www.agu.org/pubs/crossref/2008/2008GL036108.shtml

One of the most visible anthropogenic phenomena in the atmosphere is the occurrence of contrails. The direct effects of contrails on surface temperature are investigated on the basis of the data sets for the cloud cover and surface temperature over the conterminous United States for the period 1971–2001. It is shown that the increase of the average daily temperature range (DTR) over the United States during the three-day grounding period of 11–14 September 2001 cannot be attributed to the absence of contrails, a subject was debated in several previous studies. The present analysis suggests that the DTR is attributed to the change of low cloudiness.
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Mick said:
It provides additional condensation nuclei.

Is there a point to these questions? I'm happy to explain contrails, but you could just be reading up on them elsewhere.

[Edit] The additional nuclei mean there are more initial ice crystals formed. The ice crystals can only form during the initial high-humidity stage with lasts only a second or so. The more ice crystals are formed, the higher the persistence and optical density of the contrail (assuming ambient humidity is high enough for the ice crystals to grow)
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And there it is. I just deleted my last post as it repeated the question I really wanted the answer to.

This question: So the additional soot helps with contrail formation. Why?

The answer: It provides additional condensation nuclei. The additional nuclei mean there are more initial ice crystals formed. The ice crystals can only form during the initial high-humidity stage with lasts only a second or so. The more ice crystals are formed, the higher the persistence and optical density of the contrail

Lovely.

So more nuclei means more ice nucleation means more persistence, yes?
 
In this image:


001-0406074700-broken_chemtrail_sharpen.jpg

Was there any change to the make-up of the exhaust particles in the aircraft's exhaust between where the trail stops and starts again?

The particles that act as the trigger, (that cause the trapped vapour to rapidly turn to ice crystals) did they just stop?

Or was the exhaust output identical throughout, meaning that there was another cause for why the trail is intermittent?
 
With gaps like that, the cause is almost certainly flying though a thermal (a rising region of warm air, or possibly falling cold air). It's the change in the air conditions, rather than changes in the exhaust.

See:

http://contrailscience.com/broken-contrails/

And the particles are not the main cause of contrail triggering. It's the extra water in the exhaust that temporarily raises the relative humidity over 100%.
 
Mick said:
With gaps like that, the cause is almost certainly flying though a thermal (a rising region of warm air, or possibly falling cold air). It's the change in the air conditions, rather than changes in the exhaust.

See:

http://contrailscience.com/broken-contrails/

And the particles are not the main cause of contrail triggering. It's the extra water in the exhaust that temporarily raises the relative humidity over 100%.
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Yes, it's just the water vapour emitted into the right mix. The particles lead on to something a little more persistent...
 
lee h oswald said:
Yes, it's just the water vapour emitted into the right mix. The particles lead on to something a little more persistent...
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Except for the pesky fact, that the newer jet turbines burn hotter, resulting in less soot, and will make more prominent contrails than older turbojets. If particles and soot were the major factor, as you are trying to lead us into, the older turbojets with less complete combustion, would have been making bigger contrails, than modern turbofan powered aircraft do today.

So no, your speculating and semantic games where you are trying to lead us all into some kind of path where particles make contrails, is wrong.
 
lee h oswald said:
As it spreads out due to the help of the additional condensation nuclei, perhaps?
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It's complicated, but not really. The factors that cause a contrail to spread are gravity and air currents. The air currents are to some degree affected by the condensing and freezing of the water which releases latent heat (i.e. the growth of the contrail warms the air around it). Optical density also plays a part by shielding solar radiation. The size of the initial ice crystals will affect the rate of descent under gravity.

But by far the biggest factor in contrail spreading is wind shear. The increased optical density will just make it visible for longer.
 
firepilot said:
Except for the pesky fact, that the newer jet turbines burn hotter, resulting in less soot, and will make more prominent contrails than older turbojets. If particles and soot were the major factor, as you are trying to lead us into, the older turbojets with less complete combustion, would have been making bigger contrails, than modern turbofan powered aircraft do today.

So no, your speculating and semantic games where you are trying to lead us all into some kind of path where particles make contrails, is wrong.
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Yes! Well spotted! And what do you know of cloud formation? Its prerequisites? And, by the way, I thought it was that the new engines were burning a lot cooler, as Mick said on page 1:
It should have said "cooler", not "warmer". Everything else was correct though. Perhaps it would not be wise to read too much into an understandable mistake made by a non-scientific bureaucrat...
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is that you he's talking about?
 
Mick said:
With gaps like that, the cause is almost certainly flying though a thermal (a rising region of warm air, or possibly falling cold air). It's the change in the air conditions, rather than changes in the exhaust.

See:

http://contrailscience.com/broken-contrails/

And the particles are not the main cause of contrail triggering. It's the extra water in the exhaust that temporarily raises the relative humidity over 100%.
Click to expand...

Just to be clear, and to head off oswald before he dives into another semantics argument...
In the classical theory of contrail formation, the exhaust mixes with the ambient air in a linear process in temperature vs water vapour concentration space. The Clausius-Clapeyron relation tells us that the boundary between liquid and vapour phase in that space is non-linear. If the mixing line ventures across that boundary (the mixture becomes water saturated, or the RH with respect to water of the mixture becomes greater than 100%) the water vapour will condense on the readily available cloud condensation nuclei.
However, soot and nitrates also in the exhaust provide ice nuclei which contribute to ice deposition where the mixture is ice-supersaturated (RH with respect to ice greater than 100%).
Aviation and the Global Atmosphere 3.2.4. Contrail and Ice Particle Formation

To clarify a point about engine efficiency above...
Higher efficiency engines resulted in lower EGT (not more water vapour). This means the mixing starts from a lower temperature, and therefore contrails could form in warmer ambient temperature which is the mixing process end point.
See this post.
 
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Ross Marsden said:
Just to be clear, and to head off oswald before he dives into another semantics argument...
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Oh yeah. What was your question again? On the Owning (that's Owning) the Weather document? Oh yeah, this: I have read that document, too.
Quote any bit that is a "clear statement of intent", or that a particular "development will happen". Go on, quote it.

And my answer: A clear statement of intent, right at the beginning, after the acknowledgements:

Executive Summary
In 2025, US aerospace forces can “own the weather” by capitalizing on emerging technologies and
focusing development of those technologies to war-fighting applications. Such a capability offers the war
fighter tools to shape the battlespace in ways never before possible. It provides opportunities to impact
operations across the full spectrum of conflict and is pertinent to all possible futures. The purpose of this
paper is to outline a strategy for the use of a future weather-modification system to achieve military
objectives rather than to provide a detailed technical road map.




"development will happen". Go on, quote it.
ok then; from page 2 of the beginning, executive summary again:

Current technologies that will mature over the next 30 years will offer anyone who has the necessary
resources the ability to modify weather patterns and their corresponding effects




You say what? No comment?
 
Ross Marsden said:
No.
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Come on. You say that trying to have a discussion with me is like trying to herd cats, but how would you know? You never tried to discuss anything with me. You tried to lecture me a couple of times, and then you tried a couple of questions I answered in full, and then you just make snide comments. Where's the discussion? How do clouds form? You're the perfect man for the job....
 
lee h oswald said:
Come on. You say that trying to have a discussion with me is like trying to herd cats, but how would you know? You never tried to discuss anything with me. You tried to lecture me a couple of times, and then you tried a couple of questions I answered in full, and then you just make snide comments. Where's the discussion? How do clouds form? You're the perfect man for the job....
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Describe the forming of a cloud in layman's terms, I dare ya
 
lee h oswald said:
Come on. You say that trying to have a discussion with me is like trying to herd cats, but how would you know? You never tried to discuss anything with me. You tried to lecture me a couple of times, and then you tried a couple of questions I answered in full, and then you just make snide comments. Where's the discussion? How do clouds form? You're the perfect man for the job....
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We all know how clouds form. We all agree with the description in Wikipedia.

What point are you trying to make?
 
Mick said:
Because he's correct. High bypass jet engines burn hotter (and more completely, less soot), but the exhaust is cooler.

http://en.wikipedia.org/wiki/Turbofan#High-bypass_turbofan
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Exactly. Lee, do you have to waste everyones time with your semantic games and circular postings, where you often have no idea what you are talking about.

You could have just easily came up with a hypothesis, that particulate soot in jet exhaust is a major factor in contrails, and that additional particles could increase that - which is exactly where you trying to lead us. But instead you go through this whole question asking exercise, secretly thinking you are right, when you were not. However, if you had done your own research, you would have realized that the older jet turbines made much more soot than newer jet turbines, yet newer jet turbines are more prone to make contrails.

So when that is pointed out to you, you leave that behind and then try to jump on a perceived error regarding jet engine temps. You have read about cooler exhaust, and when I point out that newer jet turbines burn hotter, you have a "Ah-ha" moment, like you have got us now. Only problem is that the typical chemmie ignorance of all things aviation, yet again rears its head. On high bypass turbofan engines, often most of the flow from the jet is "bypass" air, only a smaller portion is actual jet turbine core exhaust.

You were wrong with your trying to lead us down some path of particulate matter being behind contrail persistence, and you were wrong regarding jet turbine temperatures too. And you wasted a lot of peoples time in doing so. You would do a lot better if you just made a hypothesis with some supporting points and you clearly state an actual point, or even god forbid, actually ask a question where you are trying to learn something, rather than trying to ask a question as some semantic game.
 
Mick said:
We all know how clouds form. We all agree with the description in Wikipedia.

What point are you trying to make?
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I'd like Ross to make a contribution, without sarcasm or rivalry or anything in the least 'adversarial'. Just a layman's description of how a cloud is formed, like a recipe, ingredients etc.
 
firepilot said:
Exactly. Lee, do you have to waste everyones time with your semantic games and circular postings, where you often have no idea what you are talking about.

You could have just easily came up with a hypothesis, that particulate soot in jet exhaust is a major factor in contrails, and that additional particles could increase that - which is exactly where you trying to lead us. However, if you had done your own research, you would have realized that the older jet turbines made much more soot than newer jet turbines, yet newer jet turbines are more prone to make contrails.

So when that is pointed you, you leave that behind and then try to jump on a perceived error regarding jet engine temps. You have read about cooler exhaust, and when I point out that newer jet turbines burn hotter, you have a "Ah-ha" moment, like you have got us now. Only problem is that the typical chemmie ignorance of all things aviation, yet again rears its head. On high bypass turbofan engines, often most of the flow from the jet is "bypass" air, only a smaller portion is actual jet turbine core exhaust.

You were wrong with your trying to lead us down some path of particulate matter being behind contrail persistence, and you were wrong regarding jet turbine temperatures too.
And you wasted a lot of peoples time in doing so. You would do a lot better if you just made a hypothesis with some supporting points, or even god forbid, actually ask a question where you are trying to learn something, rather than trying to ask a question as some semantic game.
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It gets better. You're making a good point. But can you tell what it is?
 
I can't quite figure lee out. He seems convinced something is going on, but can't bring himself to say what it is. I don't know why he's even posting here, unless he's simply trolling for fun.
 
Mick said:
I can't quite figure lee out. He seems convinced something is going on, but can't bring himself to say what it is. I don't know why he's even posting here, unless he's simply trolling for fun.
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All indication so far would lead to that conclusion.

If I see him ask you once more for your opinions on how clouds form I will become mildly agitated.

Cloud formation needs no opinion does it?

If it is here to derail and disrupt it will come off second best (it has) So what is it`s purpose?

Each and every question it has asked has been answered more than adequately in my opinion, talking in circles using protracted, trivial, non-specific repetition is trolling.
 
He's acting as if he's got us caught in a trap, like there's something inconsistent with the description of contrail formation vs. cloud formation, and he's trying to nudge us into saying something that he will pounce on. I strongly suspect that it will just be another misunderstanding of the basic science - like he will say "if the conditions are right for contrails to form, and contrails are clouds, then why are there no clouds?". Unfortunately he can't simply say what is objection/misunderstanding is. He has to play these ridiculous games. It's a waste of time.
 
The thing is, I don't think that he's trolling deliberately. He thinks he's cunningly talking us government shills into corners where he can reveal our inconsistencies.

Unfortunately, due to his lack of understanding of the subject he's effectively trolling.

I don't normally like to point out to anyone that they don't understand what they are talking about. I think that's a weak form of ad-hom. I prefer to show rather than tell. But in this case lees has proven impervious to being shown anything.
 
Mick said:
Seriously lee, it's not that complicated. They have cooler exhaust. They burn hotter. These two thing are not incompatible.

But again, did you have an actual point?
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Well, here's a point, somewhat pertinent to your comment above on these new engines. I quote you, from this thread, post #34 to be precise. This with regard to the proliferation of aviation induced cloud cover, you responded thus: It happens more now that it used to, sure. But ...engines run cooler

Well, it's no wonder I get confused when you are too, isn't it? So if: it's not that complicated... Then how complicated is it? Complicated enough for you to get it wrong?
 
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